def indent(node: ET.XML, level: int = 0):
i = '\n' + level * ' ' * 4
if len(node):
if not node.text or not node.text.strip():
node.text = i + ' ' * 4
if not node.tail or not node.tail.strip():
node.tail = i
for node in node:
indent(node, level + 1)
if not node.tail or not node.tail.strip():
node.tail = i
else:
if level and (not node.tail or not node.tail.strip()):
node.tail = i
